1. Field of the Invention
The present invention relates to a display system.
2. Description of the Related Art
Conventionally, an imaging apparatus is known in which a captured image is transferred to an output device and is printed/displayed. Further, a technique is known which changes an operation of an imaging apparatus based on information about an output device.
In Japanese Patent Application Laid-Open No. 2010-16552, a technique is discussed in which an imaging apparatus with a printing device overlaps a frame, which indicates the range of printing, with a captured image displayed on a liquid crystal display (LCD), in order to prevent a printed image from being cut due to a difference in an angle of view between shooting and printing.
In Japanese Patent Application Laid-Open No. 2010-16552, an imaging apparatus is discussed which changes resolution of an image to be captured corresponding to resolution of a display device externally connected.
Further, a display system in which an image captured by an imaging apparatus such as a document camera is transferred to a projection apparatus to be projected and displayed is also widely used in conference.
A projection apparatus sometimes needs to be projected being turned upward or downward from a position which does not frontally face the projection surface such as a screen when an installation place is limited or the projection apparatus is installed so as not to prevent visibility of an observer. Under such a situation, when an angle which an optical axis forms with the projection surface is different from the one set in advance or properly projectable angle, distortion occurs in an image displayed on the projection surface.
Such distortion of the projected image can be corrected in advance by executing distortion correction (trapezoid correction or keystone correction) on an image to be projected. However, this distortion correction processing is generally digital signal processing, which executes rearrangement of an image, including interpolation of a pixel and hence degrades the quality of the projected image.
When a captured image is projected by a projection apparatus, in a conventional technique, an imaging apparatus matches resolution with the projection apparatus to transfer an image to the projection apparatus. However, there is a problem that the degradation of the image quality due to the distortion correction processing in the projection apparatus cannot be avoided.